Machine for grinding and polishing spherical bodies



(No Model.)

F. W. FULLER. MACHINE FOR GRINDING AND POLISHING SPHBRIUAL BODIES.

No. 537,971, Patented. Apr. 23, 1895.

\XATNEEEEIS: NV EN TERI characters designating FREDERICK WV. FULLER, OFQUINCY, MASSACHUSETTS.

MACHINE FOR GRINDING AND POLISHING SPHERtCAL BODIES.

SPEOIIEICATION'forming part of Letters Patent No. 537,971, dated April23, 1895. A plication filed June 29, 1894. Serial No. 516,045. (Nomodel.)

To aZZ whom it may concern:

Be it known that I, FREDERICK W. FULLER, of Quincy, in the county ofNorfolk and State of Massachusetts, have invented certain new and usefulImprovements in Machines for Grinding and Polishing Spherical Bodies, ofwhich the following is a specification.

My invention relates to an improvementin machines for polishingspherical bodies for monumental architecture or other purposes, and hasfor its object, first, to provide a suitable rotary holder or cup forthe body to be operated upon; and,- second, to provide means whereby thespeed of such object may be varied relative to that of the cup.

My invention consists in certain novel features of construction andarrangement of parts, which will be fully hereinafter described andparticularly pointed out in the claims.

Reference is to be had to the accompanying drawings and the charactersmarked thereon, which form a part of this specification, like like partsor features, as the case may be, Wherever they occur.

In the drawings--Figure 1 isa perspective View of my complete machine.Fig. 2 is a front view thereof, the holder shown in section.

do are two beveled pinions suitably mounted for the transmission ofmotion from one to the other. The pinion, a, is secured to the end of ashaft, of, held upon a support, b, by bearings b. The shaft, or, andpinion, a, receive their motion through an ordinary belt connection, aThe pinion, a, is secured to a vertical shaft, or, mounted in bearings,a and a A holder or cup,f, or iron of soft metal is rigidly secured tothe upper end of the shaft by any suitable means, as for instance, by asocket in the end of the cup arranged to fit on a reduced part of theshaft, a and held together by a pin, e.

c is a stationary tray secured upon horizontal pieces, 0 c, resting uponuprights, b 5 The shaft, a, passes through the tray.

d is a lever secured to an upright, 5 by means of a bolt, 0Z Afriction-block, d, is secured upon the lever at a suitable distance fromthe pivot point to engage the ball, h,

which rests in the cup, f.

The parts being constructed and arranged as shown and described, and thespeed regulated or cup being to suit the size of the ball to be groundor polished, the machine is started, the cup,f, revolves and with it theball, h. Now, b pressing the block, cl, against the ball, h, the speedof the latter in relation to the cup will be retarded, causing theinside surface of the cup to pass about that portion of the surface ofthe ball that rests in the cup. By

supplying any suitable abrasive material at this point the ball will beground or polished as desired.

The particular parts of the surface of the ball to be presented to theaction of the abrading material at the inside surface of the cup may beregulated at will by means of the bhck, d, which when applied to theball and pressed either up or down will cause the ball to take atwisting motion in the cup, owing to the resultant of the two forces,to-witz-one tending to retard the speed of the ball in the cup,

and the downward or upward pressure of the block tending to turn theball in the cup. It will thus be seen that by pressing the block againstthe ball the surface of the ball in contact with the cup will bepolished or ground, and when it is desired to present a new surface tothe action of the abrading material this can be readily done byreleasing or increasing the pressure of the block upon the ball.

The depressiomf, in the cup serves as a receptacle fortheabradingmaterial. It is nec essary to use abrasive material of some sort sincemetal of itself will not cut stone, but merely chip or break it. Thepart, 0, serves to catch the grindings that fall from the ball, It.

Any desired form of motive power may be used, the essential thing beingthe arrangement of the rotary cup, the ball and the friction block, sothat the speed of the ball may be varied in relation to the speed of thecup, and also given a twisting motion in the cup, either forthe purposeof polishing or of changing the position of the ball in the cup.

Having thus explained the nature of my invention and described a way ofconstructing and using the same, though without attempting to set forthall of the forms in which it may be made or all of the modes of its use,what I claim, and desire to secure by Letters Patent, is-

1. In a stone polishing machine, in combination, a rotary cup forcarrying a ball, and

ICO

means for retarding the speed of the ball in relation to the speed ofthe cup, substantially as and for the purpose described.

2. In a stone polishing machine, in combination, a rotary on p forcarrying a ball, a lever provided with a friction block arranged I toengage the ball carried by said chp,"substantial'ly as and for thepurpose described.

-3. In a stone polishing machine incomb ination, a rotary cup forcarrying a ball a depressionf in the bottom of said cup to receive andhold abrasive material, a lever provided with a friction block arrangedto engage the ball carried by said cup, substantially as and for thepurpose described.

In testimony whereof I have signed my name to this specification, in thepresence of two snbscribing witnesses, this 23d day of June; A; D.1894:.

FREDERICK W. FULLER.

Witnesses:

)WILLIAM QUINBY, O. F. BROWN.

